On a dim winter afternoon in a Brooklyn tenement, a young Irish immigrant unhooks the oven gas, and inhales. In the aftermath of the fire that follows, Sister St. Savior, an ageing nun appears, unbidden, to direct the way forward for his widow and unborn child.This is how Sally comes to grow up in the convent laundry, amidst the crank of the wringer and the hiss of the iron, her universe governed by the strange, kind and mysterious Little Nursing Sisters of the Sick Poor. But although superstiti